docs: def _computeUnnormalizedLogWeights(self, u_n):
          """
          Return unnormalized log weights.
  
          REQUIRED ARGUMENTS
            u_n (N np float64 array) - reduced potential energies at single state
  
          OPTIONAL ARGUMENTS
  
          RETURN VALUES
            log_w_n (N array) - unnormalized log weights of each of a number of states
  
          REFERENCE
            'log weights' here refers to \log [ \sum_{k=1}^K N_k exp[f_k - (u_k(x_n) - u(x_n)] ]
          """
          return -1. * logsumexp(self.f_k + u_n[:, np.newaxis] - self.u_kn.T, b=self.N_k, axis=1)